1. Field of the Invention
The present disclosure generally relates to medical devices. More particularly, the disclosure relates to reinforced medical balloons.
2. Description of the Related Art
Balloon catheters are widely used in the medical profession for various intraluminal procedures. One common procedure involving the use of a balloon catheter relates to angioplasty dilation of coronary or other arteries suffering from stenosis (i.e., a narrowing of the arterial lumen that restricts blood flow).
Although balloon catheters are used in many other procedures as well, coronary angioplasty using a balloon catheter has drawn particular attention from the medical community because of the growing number of people suffering from heart problems associated with stenosis. Angioplasty procedures have become a popular alternative for treating coronary stenosis because such procedures are considerably less invasive than other alternatives. For example, stenosis of the coronary arteries has traditionally been treated with bypass surgery. In general, bypass surgery involves splitting the chest bone to open the chest cavity and grafting a replacement vessel onto the heart to bypass the blocked, or stenosed, artery.
Typically, angioplasty procedures are performed using a balloon-tipped catheter that may or may not have a stent mounted on the balloon (also referred to as a stented catheter). The physician may perform the angioplasty procedure by inserting a guide wire into a patient's body (commonly through one of the arteries in the leg) and navigating the guide wire to a diseased area. A balloon catheter may then be inserted over the guide wire and guided to the diseased area, such as a narrowed part of a coronary artery. During this stage, the balloon is uninflated and collapsed onto the shaft of the catheter in order to present a low profile which may be passed through the arterial lumens. Once the balloon is positioned at the narrowed part of the artery, the balloon is expanded by pumping an inflation solution through the catheter to the balloon. As a result, the balloon presses against the inner wall of the artery to cause dilation.
Typical inflated pressures of the balloon may range between about 6 atm to about 20 atm (i.e., 90 psi-300 psi). If a stent is mounted on the balloon, the balloon inflation also serves to expand the stent and implant it within the artery. After the artery is dilated, the balloon is deflated so that it once again collapses onto the shaft of the catheter. The balloon-tipped catheter is then retracted from the body. If a stent is mounted on the balloon of the catheter, the stent is left permanently implanted in its expanded state at the desired location in the artery to provide a support structure that prevents the artery from collapsing back to its pre-dilated condition. On the other hand, if the balloon catheter is not adapted for delivery of a stent, either a balloon-expandable stent or a self-expandable stent may be implanted in the dilated region in a follow-up procedure.
Examples of problems that may be encountered with conventional balloons relate to the balloon thickness and strength. A conventional balloon made from, for example, nylon 12 or polyethylene terephthalate (PET) may have a double wall thickness in the range of 0.04 mm to 0.1 mm. Due to the profile of such a balloon, there is limited access to certain areas of the body. Moreover, conventional materials may only allow for minimal inflation pressures and may burst if subjected to certain elevated pressures when such pressures are necessary to dilate, for example, a narrowed artery.